The present invention realtes to a composition for inducing male sterility in a plant which comprises a compound, as an active ingredient, having the formula (I): ##STR4## in whcih X is --OH, --O.sup.- M.sup.+ --OR.sup.1 or ##STR5## wherein M.sup.+ is an alkali metal cation, an alkaline earth metal cation or R1 ? ##STR6## in which R.sup.4, R.sup.5 and R.sup.6 are the same or different and each is hydrogen, a C.sub.1 -C.sub.6 alkyl, a C.sub.3 -C.sub.4 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.3 -C.sub.8 cycloalkyl, benzyl or phenyl;
R.sup.1 is a C.sub.1 -C.sub.9 alkyl, a C.sub.3 -C.sub.6 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.1 -C.sub.3 alkoxy (C.sub.1 -C.sub.4) alkyl, a C.sub.3 -C.sub.8 cycloalkyl, benzyl or phenyl; and PA1 R.sup.2 and R.sup.3 are the same or different and each is hydrogen, a C.sub.1 -C.sub.6 alkyl, a C.sub.3 -C.sub.4 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.3 -C.sub.8 cycloalkyl, a benzyl in which at most two of hydrogen atoms at the .alpha.-position thereof may be sustituted by methyl, a C.sub.2 -C.sub.3 hydroxyalkyl or a phenyl in which at most three of hydrogen atoms thereof may be substituded by the same or different C.sub.1 -C.sub.2 alkyl; PA1 Y is fluorine, chlorine, a trifluoromethyl or a C.sub.1 -C.sub.6 alkoxy; PA1 A is CF.sub.3, CHF.sub.2, CF.sub.2 Cl, CF.sub.2 BR, CF.sub.2 CHF.sub.2, CH.sub.2 CF.sub.3, CF.sub.2 CHCl.sub.2, CFClCHFCl, CF.sub.2 CHFCl or CF.sub.2 CHFCF.sub.3 ; PA1 A' is hydrogen or halogen; and PA1 W and Z are C-F and N-H respectively with non-bonding, or are taken together to form C-N, provided that X is OR.sup.1 in case that W and Z are C-F and N-H respectively, and an agriculturally accetpable carrier or diluent. PA1 R.sup.1 is a C.sub.1 -C.sub.9 alkyl, a C.sub.3 -C.sub.6 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.1 -C.sub.3 alkoxy (C.sub.1 -C.sub.4) alkyl, a C.sub.3 -C.sub.8 cycloalkyl, benzyl; and PA1 R.sup.2 and R.sup.3 are the same or different and each is hydrogen, a C.sub.1 -C.sub.6 alkyl, a C.sub.3 -C.sub.4 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.3 -C.sub.8 cycloalkyl, a benzyl in which at most two of hydrogen atoms at the .alpha.-position thereof may be substituted by methyl, a C.sub.2 -C.sub.3 hydroxyalkyl or a phenyl in which at most three of hydrogen atoms thereof may be substituted by the same or different C.sub.1 -C.sub.2 alkyl; PA1 Y is fluorine, chlorine, a trifluoromethyl or a C.sub.1 -C.sub.6 alkoxy; PA1 A is a CF.sub.3, CHF.sub.2, CF.sub.2 CL, CF.sub.2 Br, CF.sub.2 CHF.sub.2, CH.sub.2 CF.sub.3, CF.sub.2 CHCl.sub.2, CFClCHFCl, CF.sub.2 CHFCl or CF.sub.2 CHFCF.sub.3 ; PA1 A' is hydrogen or a halogen; and PA1 W and Z are C-F and N-H respectively with non-bonding, or are taken together to form C-N, provided that X is OR.sup.1 in case that W and Z are C-F and N-H respectively, and an agriculturally acceptable carrier or diluent; a method for inducing male sterility in plant, which comprises applying an effective amount of a compound having the formula (I): ##STR10## in which X is --OH, --O.sup.- M.sup.+, --OR.sup.1 or ##STR11## wherein M.sup.+ is an alkali metal cation, an alkaline earth metal cation or ##STR12## in which R.sup.4, R.sup.5 and R.sup.6 are the same or different and each is hydrogen, a C.sub.1 -C.sub.6 alkyl, a C.sub.3 -C.sub.4 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.3 -C.sub.8 cycloalkyl, benzyl or phenyl; PA1 R.sup.1 is a C.sub.1 -C.sub.9 alkyl, a C.sub.3 -C.sub.6 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.1 -C.sub.3 alkoxy (C.sub.1 -C.sub.4) alkyl group, a C.sub.3 -C.sub.8 cycloalkyl, benzyl or phenyl, and PA1 R.sup.2 and R.sup.3 are the same or different and each is hydrogen, a C.sub.1 -C.sub.6 alkyl, a C.sub.3 -C.sub.4 alkenyl, a C.sub.3 -C.sub.4 alkynyl, a C.sub.3 -C.sub.8 cycloalkyl, a benzyl in which at most two of hydrogen atoms at the .alpha.-position thereof may be susbstitued by methyl, a C.sub.2 -C.sub.3 hydroxyalkyl or a phenyl in which at most three of hydrogren atoms thereof may be substituded by the same or different C.sub.1 -C.sub.2 alkyl; PA1 Y is fluorine, chlorine, a trifluoromethyl or a C.sub.1 -C.sub.6 alkoxy; PA1 A is a CF.sub.3, CHF.sub.2, CF.sub.2 Cl, CF.sub.2 Br, CF.sub.2 CHF.sub.2, CH.sub.2 CF.sub.3, CF.sub.2 CHCl.sub.2, CFClCHFCl, CF.sub.2 CHFCl or CF.sub.2 CHFCF.sub.3 ; PA1 A' is hydrogen or a halogen; and PA1 W and Z are C-F and N-H respectively with non-bonding, or are taken together to form C-N, provided that X is OR.sup.1 in case that W and Z are C-F and N-H respectively, and an agriculturally acceptable carrier or diluent to the plant; PA1 Y is fluorine, chlorine, a trifluoromethyl or a C.sub.1 -C.sub.6 alkoxy; PA1 A is CF.sub.3, CHF.sub.2, CF.sub.2 Cl, CF.sub.2 Br, CF.sub.2 CHF.sub.2, CH.sub.2 CF.sub.3, CF.sub.2 CHCl.sub.2, CFClCHFCl, CF.sub.2 CHFCl or CF.sub.2 CHFCF.sub.3 ; and PA1 A' is hydrogen or a halogen.
In recent years, the food crisis has caused public discussion and the increase of producing food has become a big problem. Under this situation, the production of hydrid seeds has attracted attention.
It is known that the first filial generation plant has many outstanding characters such as an increased yield compared with its parent variety, owing to its vigorous growth. In order to obtain hydrid seeds it is necessary to prevent a self-pollination of a female parent and stamens of the female parent have to be removed for that purpose.
Hitherto, there have made a lot ofefforts for the operation of removing stamens, i.e. castration, and also, since grains having a high rate of self-pollination, e.g. rice, wheat, and the like, have both stamens and pistils in small spikelet, it has been almost impossible to produce the hybrid seeds manually. There are other methods such as use of a cytoplasmic male sterility, but this method has problems such as it takes a long time for its breeding. Therefore, in recent years, it has been desired simple and sure methods to induce male sterility in plant without losing a pollination ability of the female parent.
Some kinds of cinnoline derivatives are described in some lieteratures [Zh. Obshch. Khim., 37, 2487 (1967): J. Chem. Soc. Chem. Commun., 1974, 752; and Synthesis, 1983, 52]and also disclosed in EP-A No. 138661 as a chemical hydridizing agent.
However, the above mentioned compounds are not necessariuly satisfied since its efficiency is insufficient or they show a chemical injury on crop.
As the result of the continuous effort of the present inventors, now it has been found that a compound having the formula (I) can induce the male sterility in plant very simply and efficiently by treating plant with the compound. Consequently the present invention is accomplished.